Short inside fuel tank!?! Am I gonna burn up alive? 0_0
 

Hopefully someone has seen this before (and survived).

After having the RX-7 sitting on the carport since November I recently found out it wouldn't start. It turns over fine but never builds any fuel pressure (as in zero fuel pressure). Checked both fuel relays and they seem fine. Could not hear pump come on, even when jumpering F/P and GND in diagnostic box.

Well.... I was going through the service manual, testing continuity back at the fuel pump. Could not get continuity on the external pins for the connector that leads into the fuel tank. With the lid off and the pump out of the car I tested the pump and it had continuity across where the two pigtails connect after the come down from the "lid" where that connector with the pins is located. (sorry I don't have a clue what to call these)

Well I decided to unplug the pig tails from the connector on the inside of the lid and here is what I found (see pics):
Attachment 7583 Attachment 7584 Attachment 7585

I've also attached an image from the service manual showing what the photo's are of.
Attachment 7586

I need to replace the lid / connector for sure, but I'd *really* like to know what would cause something like this. I'm running a Supra fuel pump and have done the fuel pump rewire mod (fuse removed from inside block and new 20A fuse inserted into the block near the shock tower under hood). It's been that way (happily) for over 2 years. Only other wiring I had done was to add grounds as recommended in the fuel pump mod (Chuck Westbrook instructions).

Thanks for any ideas you might have!

Don't know the cause of that, but I'm looking into upgrading the plug with a high gauge wire setup. Unfortunately the one's I found are $100+. Been trying to find a Denso unit that's reasonably priced, but can't seem to find anything.

http://www.pegasusautoracing.com/gro...FUELCELLWIRING

Idk if your cars going to catch fire but if your going to dgrr can you not park next to me? LOL

Lulz, sure thing. Man after seeing that burned / melted connector I'm thinking it would be more of a dramatic fireball explosion myself. :driving:

And thanks for that link afgmoto1978, that connector looks pretty similar to the stock one. Would be nice to upgrade the wiring and know it's "fuel safe".

My plan atm is to just get a new "lid thing" with new connector and hope this was a freak occurrence. I just wish I knew how this could have happened to begin with (or when it happened exactly).

Seriously though, no one has seen this before?

Gasoline in that situation wouldn't explode. Hope that helps. :rofl:

Whoa! I used to work with a fireman who would always smoke while he filled up with gas. He said if you could breath it wouldn't ignite.... Not sure I ever wanna test that.

But thanks though for the support! Hehe. :seeya:

First off, that connector will NOT fit an FC.... trust me, I have it, I hate it, I spend ~$250/ connector for some Mil-Spec hermtically sealed connectors. They have 8 pins I believe? Each contact is rated @ 13A so i'm going to be running two wires per terminal for the pump, and two for the sender.

Also, 20A is too high a fuse rating for that wire. If that's 16ga wire, which I believe it is, it's rated for something like 15 or 17.5A depending on the shielding. Eitherway, I'd drop it down to 15A NOT 20.

Thanks TitaniumTT. :icon_tup:

I thought the stock fuse for the fuel pump (fuse block in driver side footwell) was a 20A. It's hard for me to gauge (no pun intended) the size of that wire just by eyeballing it, but I agree, it's pretty thin looking. I was just following Chuck Westbrook's guide with the choice of fuse.

Regardless, I'm gonna try starting it up tomorrow. Just finished installing a new lid w/ connector I got from David Jerome (that man has saved the day for me many times) and was able to see fuel pressure up to normal.

No explosions so I'm hoping all is well. :001_005:

What fuel pump are you running?
There needs to be about 2" of clearance between the top of the lid and the bottom of the access panel to use that fuel safe connector.
You should run an amp test at low voltage and high psi if you can to see what the pump is pulling for A and make a decision from there which fuse to use..... for some reason I thought this was an FC. FWIW my Supra pump is pulling like 12A @ 11V and 45-50psi.
For that connector to melt like that, it seems that is the symptom, not the problem, and you need to find the problem. Check the gnds, and don't ask how I know that. :banghead:

I see burnt up plugs like that constantly. Its caused by a loose connection as in one of the pins is pulled a little too far back in the connector and not making good contact. The electricity then arcs across like a spark plug gap and starts melting the plug.

when i upgraded my fuel system my wires were the same as yours. burnt.
scary.